ATT / Nokia BGW320-505 Range Extender recommendations, please

[rmnc3r]

I upgraded(?) to ATT FO and their new Nokia BGW320-505 Gateway won't work with my old Airties 4920.
ATT will help 'solve the probelm' by leasing their branded extenders for $10/mo. No Thanks!
Google AI says ATT uses Airties Air 4971 - is this correct?

Would some kind forum Technologist please suggest a cost effective (meaning 'cheap') range extender suitable for a 2 story, 2500 sq ft Building?

The Gateway is on the 2nd Floor on one side of the Building and the Range Extender would mostly be used for Laptops and Devices on the first floor, opposite side of the Building

[ibanezfoo]

We have never had good luck with range extenders. You can setup a mesh network pretty cheap now. Pick your favorite brand, they all work pretty well these days. Depending on your walls you'd only need two or three pucks. My house is about the same and I just use two pucks. One upstairs in one corner, and the other downstairs in the other corner.